ADIF (Amateur Data Interchange Format) -- A log-data file format that many log programs can output. See http://www.hosenose.com/adif/ for details.
Cabrillo -- A log-data file format used for the submission of contest logs. See http://www.kkn.net/~trey/cabrillo/ for details.
Digital Certificate -- A file that contains a unique set of signing keys to be used for creating digital signatures.
Digital Signature -- A data block that uniquely ties a digital certificate to a specific message (block of text or data). Using the digital signature and its associated digital certificate, TrustedQSL programs can verify that the message was signed by the holder of the certificate and that the message was not altered after being signed.
Signing -- Creating a digital signature of a message (a block of text or data). In TrustedQSL, the QSO data records are signed.
Station Location -- A station location describes call sign, geographic location and political subdivisions of a particular station operation. Station locations are tied to digital certificates, which in turn contain the station call sign and DXCC entity. There may be more than one station location for a particular call-sign/dxcc-entity, allowing for portable and mobile operation.